19 Jul
2024
19 Jul
'24
10:52 p.m.
Last month, I got to speak at VCF SW on aspects about the history of
personal computers.
https://www.youtube.com/watch?v=fpF6Ofrr6_0
(I botched a couple things, a link to corrections is in the Description)
I brought up the 1968 book "How to build a working digital
computer"(Alcosser). I was wondering about opinions here on that book -
was it at all influential at the time? Or is anyone aware of actually
building the system it describes?
And - any thoughts on "digital computer" vs analog? I'm aware of early
Heathkit analog computers. Is it fair to say quantum computing is sort of
a return back to analog computing?
I recently heard someone make a comment that we're near the end of the
"3.3V era" (maybe this was in the recent X16 talk, where some of the
challenges of the recent retro-remakes is exploring back to the 5V era and
how it's getting more difficult to find modern-make components that support
that).
Has no one explored a "tri-state" system? (discrete regions across 5V?)
- Steve
(v* voidstar tech, not to be confused with voidstar labs)
20 Jul
20 Jul
2:05 a.m.
Steve
You ask a lot of good questions.
The story is pretty well documented. There was a company that made a
commercial version of the computer described in the book
https://blog.adafruit.com/2013/05/08/how-to-build-a-working-digital-compute…
There is a nice paperclip computer at the System Source museum in Hunt
Valley, MD.
I am sure there are people who actually built homebrew versions by
following the book but I have never seen one.
Analog computers are not like quantum computers enough for a valid
comparison. Different era, different uses. Quantum computers are still
digital computers and they're really nothing like analog computers of the
50's-late 60's.
Analog computers were wired to complete a circuit that performs a
mathematical function circuit. The inputs and outputs are voltages or
other electronically-measurable forces such as vibration. When an analog
computer program runs the output is sent to a voltmeter, oscilloscope,
plotter or counter, or custom device. A person would take the plot (waves,
plotted points, etc.) and measure the slope or wave frequency manually by
performing additional calculations with a slide rule or feeding the data
into a digital computer for analysis. Think smart programmable thermostat.
Analog computers are more like open-use peripherals that can be programmed
to do one thing at a time over and over. Analog computers often
had amplifier tubes which were used to generate input voltage pulses to be
fed into the program circuitry. I am just touching the surface, but hope
that explains what they did. They're no longer used for general computing
because now we have USB devices that do analog to digital conversion
50's-60s' analog computer programming is done by patch panel.
BIll
On Fri, Jul 19, 2024 at 10:58 PM Steve Lewis via cctalk <
cctalk(a)classiccmp.org> wrote:
Last month, I got to speak at VCF SW on aspects about
the history of
personal computers.
https://www.youtube.com/watch?v=fpF6Ofrr6_0
(I botched a couple things, a link to corrections is in the Description)
I brought up the 1968 book "How to build a working digital
computer"(Alcosser). I was wondering about opinions here on that book -
was it at all influential at the time? Or is anyone aware of actually
building the system it describes?
And - any thoughts on "digital computer" vs analog? I'm aware of early
Heathkit analog computers. Is it fair to say quantum computing is sort of
a return back to analog computing?
I recently heard someone make a comment that we're near the end of the
"3.3V era" (maybe this was in the recent X16 talk, where some of the
challenges of the recent retro-remakes is exploring back to the 5V era and
how it's getting more difficult to find modern-make components that support
that).
Has no one explored a "tri-state" system? (discrete regions across 5V?)
- Steve
(v* voidstar tech, not to be confused with voidstar labs)
2:06 a.m.
I should add, the paperclip computer was a mechanical computer, not an
analog computer in the 50-60's sense of the term.
b
On Sat, Jul 20, 2024 at 2:05 AM Bill Degnan <billdegnan(a)gmail.com> wrote:
Steve
You ask a lot of good questions.
The story is pretty well documented. There was a company that made a
commercial version of the computer described in the book
https://blog.adafruit.com/2013/05/08/how-to-build-a-working-digital-compute…
There is a nice paperclip computer at the System Source museum in Hunt
Valley, MD.
I am sure there are people who actually built homebrew versions by
following the book but I have never seen one.
Analog computers are not like quantum computers enough for a valid
comparison. Different era, different uses. Quantum computers are still
digital computers and they're really nothing like analog computers of the
50's-late 60's.
Analog computers were wired to complete a circuit that performs a
mathematical function circuit. The inputs and outputs are voltages or
other electronically-measurable forces such as vibration. When an analog
computer program runs the output is sent to a voltmeter, oscilloscope,
plotter or counter, or custom device. A person would take the plot (waves,
plotted points, etc.) and measure the slope or wave frequency manually by
performing additional calculations with a slide rule or feeding the data
into a digital computer for analysis. Think smart programmable thermostat.
Analog computers are more like open-use peripherals that can be programmed
to do one thing at a time over and over. Analog computers often
had amplifier tubes which were used to generate input voltage pulses to be
fed into the program circuitry. I am just touching the surface, but hope
that explains what they did. They're no longer used for general computing
because now we have USB devices that do analog to digital conversion
50's-60s' analog computer programming is done by patch panel.
BIll
On Fri, Jul 19, 2024 at 10:58 PM Steve Lewis via cctalk <
cctalk(a)classiccmp.org> wrote:
Last month, I got to speak at VCF SW on aspects
about the history of
personal computers.
https://www.youtube.com/watch?v=fpF6Ofrr6_0
(I botched a couple things, a link to corrections is in the Description)
I brought up the 1968 book "How to build a working digital
computer"(Alcosser). I was wondering about opinions here on that book -
was it at all influential at the time? Or is anyone aware of actually
building the system it describes?
And - any thoughts on "digital computer" vs analog? I'm aware of early
Heathkit analog computers. Is it fair to say quantum computing is sort of
a return back to analog computing?
I recently heard someone make a comment that we're near the end of the
"3.3V era" (maybe this was in the recent X16 talk, where some of the
challenges of the recent retro-remakes is exploring back to the 5V era and
how it's getting more difficult to find modern-make components that
support
that).
Has no one explored a "tri-state" system? (discrete regions across 5V?)
- Steve
(v* voidstar tech, not to be confused with voidstar labs)
6:46 p.m.
A fair clarification, I realize that I was sort of mixing two different
topics (and didn't mean to imply it had anything to do with analog
computing).
What I meant was that in the title of the book they use "digital computer"
and I wonder if there was ever a book describing a mechanical "analog
computer" - and what they might even look like.
It's also funny to me they've inserted the word "working" (I wonder if
that
was a subtle tribute to the Babbage machine, which at the time wasn't
confirmed to be a working system -- I've read that the Mark-1 was largely
inspired as an intent to realize the Analytic Engine, but the Mark-1 does
include numerous "electro" upgrades probably to make the implementation far
more practical and more useful in the end).
and - thanks on the notes for ternary computers (and also references to
where this "paperclip computer" has been realized in the past!).
-Steve
On Sat, Jul 20, 2024 at 2:03 PM Bill Degnan via cctalk <
cctalk(a)classiccmp.org> wrote:
I should add, the paperclip computer was a mechanical
computer, not an
analog computer in the 50-60's sense of the term.
b
On Sat, Jul 20, 2024 at 2:05 AM Bill Degnan <billdegnan(a)gmail.com> wrote:
Steve
You ask a lot of good questions.
The story is pretty well documented. There was a company that made a
commercial version of the computer described in the book
https://blog.adafruit.com/2013/05/08/how-to-build-a-working-digital-compute…
There is a nice paperclip computer at the System
Source museum in Hunt
Valley, MD.
I am sure there are people who actually built homebrew versions by
following the book but I have never seen one.
Analog computers are not like quantum computers enough for a valid
comparison. Different era, different uses. Quantum computers are still
digital computers and they're really nothing like analog computers of the
50's-late 60's.
Analog computers were wired to complete a circuit that performs a
mathematical function circuit. The inputs and outputs are voltages or
other electronically-measurable forces such as vibration. When an analog
computer program runs the output is sent to a voltmeter, oscilloscope,
plotter or counter, or custom device. A person would take the plot
(waves,
plotted points, etc.) and measure the slope or
wave frequency manually by
performing additional calculations with a slide rule or feeding the data
into a digital computer for analysis. Think smart programmable
thermostat.
Analog computers are more like open-use peripherals that can be
programmed
to do one thing at a time over and over. Analog
computers often
had amplifier tubes which were used to generate input voltage pulses to
be
fed into the program circuitry. I am just
touching the surface, but hope
that explains what they did. They're no longer used for general
computing
because now we have USB devices that do analog to
digital conversion
50's-60s' analog computer programming is done by patch panel.
BIll
On Fri, Jul 19, 2024 at 10:58 PM Steve Lewis via cctalk <
cctalk(a)classiccmp.org> wrote:
> Last month, I got to speak at VCF SW on aspects about the history of
> personal computers.
> https://www.youtube.com/watch?v=fpF6Ofrr6_0
> (I botched a couple things, a link to corrections is in the Description)
>
> I brought up the 1968 book "How to build a working digital
> computer"(Alcosser). I was wondering about opinions here on that book -
> was it at all influential at the time? Or is anyone aware of
actually
> building the system it describes?
>
> And - any thoughts on "digital computer" vs analog? I'm aware of
early
> Heathkit analog computers. Is it fair to say quantum computing is sort
of
> a return back to analog computing?
>
> I recently heard someone make a comment that we're near the end of the
> "3.3V era" (maybe this was in the recent X16 talk, where some of the
> challenges of the recent retro-remakes is exploring back to the 5V era
and
how
it's getting more difficult to find modern-make components that
support
that).
Has no one explored a "tri-state" system? (discrete regions across 5V?)
- Steve
(v* voidstar tech, not to be confused with voidstar labs)
10:04 p.m.
On Sat, 20 Jul 2024, Steve Lewis via cctalk wrote:
What I meant was that in the title of the book they
use "digital computer"
and I wonder if there was ever a book describing a mechanical "analog
computer" - and what they might even look like.
half a century ago, my cousin showed me some plexiglas blocks with odd
shaped holes through them, and said that they were from an experimental
analog computer. I guess that you could figure out fluid behavior by
making analogies to electronics - amount of flow is kinda like current,
amount of head or pressure is kinda like voltage, restrictions are kinda
like resistance, one way valves are diodes, . . .
10:29 p.m.
Instead of paper clips and cardboard, consider a pachinko like marble
based computer. (claimed to be Turing complete, if you expand it enough)
https://upperstory.com/en/turingtumble
It's bulkier than a mobile phone.
or relays? :
https://www.amazon.com/Giant-brains-Machines-that-think/dp/B0006AS6Q4
Giant Brains : or Machines That Think
by Edmund C. Berkeley
His Simon computer was a relay based (a bit limited for modern uses), but
was an early (1950) electro-mechanical personal computer.
21 Jul
21 Jul
12:41 a.m.
On Sun, Jul 21, 2024 at 3:08 AM Steve Lewis via cctalk
<cctalk(a)classiccmp.org> wrote:
What I meant was that in the title of the book they
use "digital computer"
and I wonder if there was ever a book describing a mechanical "analog
computer" - and what they might even look like.
There have been mechanical analogue computers and I have at least one
book describing them on my shelves.
Typically they used disc integrators with an igenious arrangement of
strings and drums as a torque amplifier. These were then coupled by
gearing which had to be set up for each problem (simple gear trains
correspond to fixed gain amplifiers, differential gear trains to
differential amplfiiers, etc).
I doubt you could make one from cardboard, but there was at least one
UK University that made a simple one from Meccano (similar to Erector
Sets across the Pond?). It was on show, not operating, in the London
Science Museum at one time, but I think it's in storage now,
-tony
1:03 a.m.
On 2024-07-20 10:41 p.m., Tony Duell via cctalk wrote:
On Sun, Jul 21, 2024 at 3:08 AM Steve Lewis via
cctalk
<cctalk(a)classiccmp.org> wrote:
Fluid computing, tech of the future.
Or it was in 1968...
What I meant was that in the title of the book
they use "digital computer"
and I wonder if there was ever a book describing a mechanical "analog
computer" - and what they might even look like.
There have been mechanical analogue computers and I have at least one
book describing them on my shelves.
Typically they used disc integrators with an igenious arrangement of
strings and drums as a torque amplifier. These were then coupled by
gearing which had to be set up for each problem (simple gear trains
correspond to fixed gain amplifiers, differential gear trains to
differential amplfiiers, etc).
I doubt you could make one from cardboard, but there was at least one
UK University that made a simple one from Meccano (similar to Erector
Sets across the Pond?). It was on show, not operating, in the London
Science Museum at one time, but I think it's in storage now,
-tony 
3:45 a.m.
-----Original Message-----
From: Tony Duell via cctalk <cctalk(a)classiccmp.org>
Sent: Sunday, July 21, 2024 5:42 AM
To: General Discussion: On-Topic and Off-Topic Posts <cctalk(a)classiccmp.org>
Cc: Steve Lewis <lewissa78(a)gmail.com>om>; Tony Duell
<ard.p850ug1(a)gmail.com>
Subject: [cctalk] Re: the 1968 how to build a working digital computer
On Sun, Jul 21, 2024 at 3:08 AM Steve Lewis via cctalk <cctalk(a)classiccmp.org>
wrote:
Several people have made Analog Computers from Meccano. The "first" I think was
at Manchester University in the UK intended as a prototype or proof of concept it was
later replaced by an engineered device.
Both were on display in the Science Museum but I believe they are now in Storage.
Cambridge University UK also had a Meccano Analog Computer. I believe this is the one now
on display at MOTAT, Aukland, New Zealand
https://motat.nz/
there are some pictures of it on my one drive (if it asks you to sign in and you don't
wish to use an incognito window)
https://1drv.ms/f/s!Ag4BJfE5B3onlsxny71p3CPOQV4svA?e=aSdamK
in more recent times Tim Robinson built one...
https://www.meccano.us/differential_analyzers/robinson_da/index.html
.. so there are some clues on how to do it about, but no book as far as I know
What I meant was that in the title of the book
they use "digital computer"
and I wonder if there was ever a book describing a mechanical "analog
computer" - and what they might even look like.
There have been mechanical analogue computers and I have at least one book
describing them on my shelves.
Typically they used disc integrators with an igenious arrangement of strings and
drums as a torque amplifier. These were then coupled by gearing which had to
be set up for each problem (simple gear trains correspond to fixed gain
amplifiers, differential gear trains to differential amplfiiers, etc).
I doubt you could make one from cardboard, but there was at least one UK
University that made a simple one from Meccano (similar to Erector Sets across
the Pond?). It was on show, not operating, in the London Science Museum at
one time, but I think it's in storage now,
-tony
Dave
G4UGM
5:39 a.m.
I think when the book was written, digital computers were the latest tech
and analog computers had been actually pretty common for 30 years.
Technology included fluid (
https://www.sciencemuseum.org.uk/objects-and-stories/how-does-economy-work),
mechanical (https://en.wikipedia.org/wiki/Kerrison_Predictor) and
electronic.
I don't think the title was related to the analytical engine, my take would
be that it was just an encouragement to the reader that it was an
achievable and usable device.
It may be that the military uses contributed to the lack of public
documentation of the mechanical systems.
On Sun, Jul 21, 2024 at 9:03 AM Dave Wade G4UGM via cctalk <
cctalk(a)classiccmp.org> wrote:
book
-----Original Message-----
From: Tony Duell via cctalk <cctalk(a)classiccmp.org>
Sent: Sunday, July 21, 2024 5:42 AM
To: General Discussion: On-Topic and Off-Topic Posts <
cctalk(a)classiccmp.org>
Cc: Steve Lewis <lewissa78(a)gmail.com>om>; Tony
Duell
<ard.p850ug1(a)gmail.com>
Subject: [cctalk] Re: the 1968 how to build a working digital computer
On Sun, Jul 21, 2024 at 3:08 AM Steve Lewis via cctalk <
cctalk(a)classiccmp.org>
wrote:
> What I meant was that in the title of the book they use "digital
computer"
and I
wonder if there was ever a book describing a mechanical "analog
computer" - and what they might even look like.
There have been mechanical analogue computers and I have at least one
describing them on my shelves.
Typically they used disc integrators with an igenious arrangement of
strings and
drums as a torque amplifier. These were then
coupled by gearing which
had to
be set up for each problem (simple gear trains
correspond to fixed gain
amplifiers, differential gear trains to differential amplfiiers, etc).
I doubt you could make one from cardboard, but there was at least one UK
University that made a simple one from Meccano (similar to Erector Sets
across
the Pond?). It was on show, not operating, in the
London Science Museum
at
one time, but I think it's in storage now,
Several people have made Analog Computers from Meccano. The "first" I
think was at Manchester University in the UK intended as a prototype or
proof of concept it was later replaced by an engineered device.
Both were on display in the Science Museum but I believe they are now in
Storage. Cambridge University UK also had a Meccano Analog Computer. I
believe this is the one now on display at MOTAT, Aukland, New Zealand
https://motat.nz/
there are some pictures of it on my one drive (if it asks you to sign in
and you don't wish to use an incognito window)
https://1drv.ms/f/s!Ag4BJfE5B3onlsxny71p3CPOQV4svA?e=aSdamK
in more recent times Tim Robinson built one...
https://www.meccano.us/differential_analyzers/robinson_da/index.html
.. so there are some clues on how to do it about, but no book as far as I
know
-tony
Dave
G4UGM
20 Jul
20 Jul
6:23 p.m.
Adrian: Fair point on the possible military-uses. I think that's an aspect
we often forget about today, compared to back then and "height of the cold
war" era. The world was "smaller" then (1950s/1960s) in terms of
population being easier to control. Bear with me: what I mean is, it
seems then government was far more concerned about technologies and ideas
getting into foreign hands. I don't run a business and don't know
anything about foreign trade - but "from the outside" it just seems back
then, there was a lot more scrutiny on such things in comparison to today.
Computers (or "data processing systems" in general) were definitely a
competitive advantage that you wouldn't want your adversaries to have.
A few years ago I got a FLIR camera, and on the back it says "export
controlled" It's the only consumer-device I ever got that has an explicit
Export Controlled sticker on it. I imagine if I were to bring it with me
on a trip to China, that probably wouldn't go well. Combined also there
was a bit more honor in representing your product (back then). Meaning, if
you called a little box of wires a computer, first people would claim false
advertisement, and second government agents would be interested to know
what you're up to (I didn't live in the 50s, so I suspect some of that is a
bit hyperbole - but my point is that in contrast today, false-advertisement
is kind of the norm and it takes quite a lot for a good ol'e FBI raid these
days).
(and to clarify - there are some good ads and good products out there, what
I mean is there doesn't seem to be much in consequences to
false-advertisement, and you can't just bad-mouth that company with the
bad-product because they can quickly just morph into another name -- like
those cheap $50 "amazing" drones that they claim can do everything a $1000
Mavic Pro can do, mmmhmmmm.... or that CyberTruck is starting to look a bit
suspect on the claims it had, but who knows, a little firmware update might
solve it all)
Actually I haven't checked - do the authors of that book happen to still be
around? I'm on the road today, will have to look more into that later
tonight.
On Sun, Jul 21, 2024 at 7:08 AM Adrian Godwin via cctalk <
cctalk(a)classiccmp.org> wrote:
I think when the book was written, digital computers
were the latest tech
and analog computers had been actually pretty common for 30 years.
Technology included fluid (
https://www.sciencemuseum.org.uk/objects-and-stories/how-does-economy-work
),
mechanical (https://en.wikipedia.org/wiki/Kerrison_Predictor) and
electronic.
I don't think the title was related to the analytical engine, my take would
be that it was just an encouragement to the reader that it was an
achievable and usable device.
It may be that the military uses contributed to the lack of public
documentation of the mechanical systems.
On Sun, Jul 21, 2024 at 9:03 AM Dave Wade G4UGM via cctalk <
cctalk(a)classiccmp.org> wrote:
book
UK
-----Original Message-----
From: Tony Duell via cctalk <cctalk(a)classiccmp.org>
Sent: Sunday, July 21, 2024 5:42 AM
To: General Discussion: On-Topic and Off-Topic Posts <
cctalk(a)classiccmp.org>
Cc: Steve Lewis <lewissa78(a)gmail.com>om>; Tony
Duell
<ard.p850ug1(a)gmail.com>
Subject: [cctalk] Re: the 1968 how to build a working digital computer
On Sun, Jul 21, 2024 at 3:08 AM Steve Lewis via cctalk <
cctalk(a)classiccmp.org>
wrote:
> What I meant was that in the title of the book they use "digital
computer"
and I
wonder if there was ever a book describing a mechanical "analog
computer" - and what they might even look like.
There have been mechanical analogue computers and I have at least one
describing them on my shelves.
Typically they used disc integrators with an igenious arrangement of
strings and
drums as a torque amplifier. These were then
coupled by gearing which
had to
> be set up for each problem (simple gear trains correspond to fixed gain
> amplifiers, differential gear trains to differential amplfiiers, etc).
>
> I doubt you could make one from cardboard, but there was at least one
University that made a simple one from Meccano (similar to Erector Sets
across
the Pond?). It was on show, not operating, in the
London Science Museum
at
one time, but I think it's in storage now,
Several people have made Analog Computers from Meccano. The "first" I
think was at Manchester University in the UK intended as a prototype or
proof of concept it was later replaced by an engineered device.
Both were on display in the Science Museum but I believe they are now in
Storage. Cambridge University UK also had a Meccano Analog Computer. I
believe this is the one now on display at MOTAT, Aukland, New Zealand
https://motat.nz/
there are some pictures of it on my one drive (if it asks you to sign in
and you don't wish to use an incognito window)
https://1drv.ms/f/s!Ag4BJfE5B3onlsxny71p3CPOQV4svA?e=aSdamK
in more recent times Tim Robinson built one...
https://www.meccano.us/differential_analyzers/robinson_da/index.html
.. so there are some clues on how to do it about, but no book as far as I
know
-tony
Dave
G4UGM
21 Jul
21 Jul
1:32 p.m.
On 21/07/2024 00:23, Steve Lewis via cctalk wrote:
A few years ago I got a FLIR camera, and on the back
it says "export
controlled" It's the only consumer-device I ever got that has an explicit
Export Controlled sticker on it. I imagine if I were to bring it with me
on a trip to China, that probably wouldn't go well.
I remember back in 1990 or so in the last years of the Soviet Union
when I was over in Moscow to help organize the first Soviet UNIX
conference. In the list of stuff we were not allowed to bring was
the Yamaha DX7 music synthesizer and the Apple LaserWriter. Both
had too much CPU power...
Julf
9:25 p.m.
New subject: Need Car/Truck space for two DEC size boxes from Chico, Ca to the Chicago area
I recently purchased a PDP-8/L and an expansion box from a very nice
gentleman in Chico, California and I need a way to get it to Chicago.
If you are driving from Chico, California to Chicago (for VCFMW or just
because) and you have room in your car/truck for two 10" High x 19" wide
x 24" deep metal boxes plus two small cardboard boxes and are willing to
make a stop in Chico to pick up the items I would be very happy to
contribute to gas/truck rental.
I can drive to meet you if you are coming withing 100 miles of Chicago.
Please contact me off list at bitwiz(a)12bitsbest.com to make arrangements.
Thank you,
Mike.
10:29 a.m.
I'm pretty sure the book included "Working" in the title because who wants
to build a non-working computer?
Also, mechanical analog computer = slide rule :)
Sellam
On Sun, Jul 21, 2024, 5:08 AM Adrian Godwin via cctalk <
cctalk(a)classiccmp.org> wrote:
I think when the book was written, digital computers
were the latest tech
and analog computers had been actually pretty common for 30 years.
Technology included fluid (
https://www.sciencemuseum.org.uk/objects-and-stories/how-does-economy-work
),
mechanical (https://en.wikipedia.org/wiki/Kerrison_Predictor) and
electronic.
I don't think the title was related to the analytical engine, my take would
be that it was just an encouragement to the reader that it was an
achievable and usable device.
It may be that the military uses contributed to the lack of public
documentation of the mechanical systems.
On Sun, Jul 21, 2024 at 9:03 AM Dave Wade G4UGM via cctalk <
cctalk(a)classiccmp.org> wrote:
book
UK
-----Original Message-----
From: Tony Duell via cctalk <cctalk(a)classiccmp.org>
Sent: Sunday, July 21, 2024 5:42 AM
To: General Discussion: On-Topic and Off-Topic Posts <
cctalk(a)classiccmp.org>
Cc: Steve Lewis <lewissa78(a)gmail.com>om>; Tony
Duell
<ard.p850ug1(a)gmail.com>
Subject: [cctalk] Re: the 1968 how to build a working digital computer
On Sun, Jul 21, 2024 at 3:08 AM Steve Lewis via cctalk <
cctalk(a)classiccmp.org>
wrote:
> What I meant was that in the title of the book they use "digital
computer"
and I
wonder if there was ever a book describing a mechanical "analog
computer" - and what they might even look like.
There have been mechanical analogue computers and I have at least one
describing them on my shelves.
Typically they used disc integrators with an igenious arrangement of
strings and
drums as a torque amplifier. These were then
coupled by gearing which
had to
> be set up for each problem (simple gear trains correspond to fixed gain
> amplifiers, differential gear trains to differential amplfiiers, etc).
>
> I doubt you could make one from cardboard, but there was at least one
University that made a simple one from Meccano (similar to Erector Sets
across
the Pond?). It was on show, not operating, in the
London Science Museum
at
one time, but I think it's in storage now,
Several people have made Analog Computers from Meccano. The "first" I
think was at Manchester University in the UK intended as a prototype or
proof of concept it was later replaced by an engineered device.
Both were on display in the Science Museum but I believe they are now in
Storage. Cambridge University UK also had a Meccano Analog Computer. I
believe this is the one now on display at MOTAT, Aukland, New Zealand
https://motat.nz/
there are some pictures of it on my one drive (if it asks you to sign in
and you don't wish to use an incognito window)
https://1drv.ms/f/s!Ag4BJfE5B3onlsxny71p3CPOQV4svA?e=aSdamK
in more recent times Tim Robinson built one...
https://www.meccano.us/differential_analyzers/robinson_da/index.html
.. so there are some clues on how to do it about, but no book as far as I
know
-tony
Dave
G4UGM
7:37 p.m.
On Sat, Jul 20, 2024, 9:08 PM Steve Lewis via cctalk <cctalk(a)classiccmp.org
wrote:
A fair clarification, I realize that I was sort of
mixing two different
topics (and didn't mean to imply it had anything to do with analog
computing).
What I meant was that in the title of the book they use "digital computer"
and I wonder if there was ever a book describing a mechanical "analog
computer" - and what they might even look like.
-Steve
Not retro but when the Goodwill Computer Museum (in Austin) had a
knowledgeable team running it they spun off into the Museum of Computer
Culture and had created a relay computer the RC3. (They did this while at
goodwill but right before the museum got shutdown as it wasn't making the
goodwill owners enough money). Unfortunately now the MCC site is also down
but a nice reference with a running video (it was loud) but impressive can
be found here https://austin.makerfaire.com/maker/entry/709/
There's another relay computer here (I'm not as familiar with) but read
that it was a good amount of information around it, maybe it references an
early book somewhere. http://web.cecs.pdx.edu/~harry/Relay/index.html
Confusing myself as I thought about it, what category is a relay computer?
It's electric and I would say mechanical but then not sure if mechanical
can be electric. Is it still analog?
- John
7:49 p.m.
On Sun, 21 Jul 2024, John Herron via cctalk wrote:
Not retro but when the Goodwill Computer Museum (in
Austin) had a
knowledgeable team running it they spun off into the Museum of Computer
Culture and had created a relay computer the RC3. (They did this while at
goodwill but right before the museum got shutdown as it wasn't making the
goodwill owners enough money). Unfortunately now the MCC site is also down
but a nice reference with a running video (it was loud) but impressive can
be found here https://austin.makerfaire.com/maker/entry/709/
There's another relay computer here (I'm not as familiar with) but read
that it was a good amount of information around it, maybe it references an
early book somewhere. http://web.cecs.pdx.edu/~harry/Relay/index.html
Confusing myself as I thought about it, what category is a relay computer?
It's electric and I would say mechanical but then not sure if mechanical
can be electric. Is it still analog?
Relays are mechanical.
Relays are electric, but, are they "electronic"?
They are intrinically digital, not analog, but perhaps a hybrid could be
built, with analog registers, but digital addreessing?
In the late 1960s, I tried to build a photo enlarging/printing exposure
and color balance meter, with wheatstone bridges and relays for a crude
homemade analog to digital conversion.
I got it to work at a proof of concept level, but not well enough to
actually be of use.
--
Grumpy Ol' Fred cisin(a)xenosoft.com
7:53 p.m.
Confusing myself as I thought about it, what category
is a relay computer?
It's electric and I would say mechanical but then not sure if mechanical can be
electric.
Is it still analog?
It's digital, in the sense that it operates on data that is encoded into discrete
values, as opposed to operating on continuous data elements, which would be analog.
I would classify it as an electromechanical digital computer. Also, it's pretty neat,
and I want one!
-mike
22 Jul
22 Jul
9:06 p.m.
Besides slide rules, etc.
If you have an analog computer consisting of a 5 gallon bucket, and a 3
gallon bucket, and plenty of water available,
What are the steps for a PROGRAM to get a result of 4 gallons of water in
the 5 gallon bucket?
9:18 p.m.
On 2024-07-22 7:06 p.m., Fred Cisin via cctalk wrote:
Besides slide rules, etc.
If you have an analog computer consisting of a 5 gallon bucket, and a 3
gallon bucket, and plenty of water available, What are the steps for a
PROGRAM to get a result of 4 gallons of water in the 5 gallon bucket?
Step 1: Get a cowboy with a 10 gallon hat.:)
9:32 p.m.
It was thus said that the Great Fred Cisin via cctalk once stated:
Besides slide rules, etc.
If you have an analog computer consisting of a 5 gallon bucket, and a 3
gallon bucket, and plenty of water available,
What are the steps for a PROGRAM to get a result of 4 gallons of water in
the 5 gallon bucket?
1. Fill 5g bucket
2. Fill 3g bucket from 5g bucket
3. Empty 3g bucket
4. Fill 3g bucket from 5g bucket (3g bucket will have 2g after)
5. Fill 5g bucket
6. Fill 3g bucket from 5g bucket.
This will leave 4g in the 5g bucket, and 3g in the 3g bucket.
-spc
21 Jul
21 Jul
8:43 p.m.
Not retro but when the Goodwill Computer Museum (in
Austin) had a
knowledgeable team running it they spun off into the Museum of Computer
Culture and had created a relay computer the RC3. (They did this while at
goodwill but right before the museum got shutdown as it wasn't making the
goodwill owners enough money). Unfortunately now the MCC site is also down
but a nice reference with a running video (it was loud) but impressive can
be found herehttps://austin.makerfaire.com/maker/entry/709/
There's another relay computer here (I'm not as familiar with) but read
that it was a good amount of information around it, maybe it references an
early book somewhere.http://web.cecs.pdx.edu/~harry/Relay/index.html
Confusing myself as I thought about it, what category is a relay computer?
It's electric and I would say mechanical but then not sure if mechanical
can be electric. Is it still analog?
- John
I would say digital a common relay has two states open or closed, when
you energize the coil it draws in the armature which will open or close
the relay's contacts.
Konrad Zuse built his first digital computer using largely relay logic
in 1940, but his work was not widely known until well after WWII due to
him working mostly by himself in Germany. He was aware that vacuum
tubes could be used as logic elements, even having one demonstrated to
him by a friend, but stuck with relays as they where easier to obtain.
On a trip to Japan CuriousMarc was shown a Japanese relay computer FACOM
128B built in 1958 and still operational.
https://www.youtube.com/watch?v=_j544ELauus
Paul.
22 Jul
22 Jul
12:09 a.m.
On 2024-07-21 6:43 p.m., Paul Berger via cctalk wrote:
I would say digital a common relay has two states open
or closed, when
you energize the coil it draws in the armature which will open or close
the relay's contacts.
Konrad Zuse built his first digital computer using largely relay logic
in 1940, but his work was not widely known until well after WWII due to
him working mostly by himself in Germany. He was aware that vacuum
tubes could be used as logic elements, even having one demonstrated to
him by a friend, but stuck with relays as they where easier to obtain.
All of Zuse's machines are digital. I find his mechanical memory most
interesting.
Paul.
Quote on the Z1
There is a replica of this Model in the Museum of
Traffic and Technology in Berlin. Back then it didn't function well, and in that
regard the replica is very reliable — it also doesn't work well.
— Konrad Zuse
Ben.
8:53 p.m.
On Sat, Jul 20, 2024 at 8:08 PM Steve Lewis via cctalk <
cctalk(a)classiccmp.org> wrote:
What I meant was that in the title of the book they
use "digital computer"
and I wonder if there was ever a book describing a mechanical "analog
computer" - and what they might even look like.
I haven't looked for a book, but if you'll settle for Wikipedia:
https://en.wikipedia.org/wiki/Differential_analyser
10:30 p.m.
At the last vcf here in California a fellow, I forget the name, brought in two tables that
connected together, could generate a damped sine wave. It used mostly Manco erector like
parts. It had some really great 0 backlash torque multipliers. They had to be finely tuned
so as to have almost 0 load on the integrating disk.
WW2 fire control computers were used on US battle ships. They had to compensate for things
like coriolis effects, mass, distance and charge.
Dwight
________________________________
From: Eric Smith via cctalk <cctalk(a)classiccmp.org>
Sent: Monday, July 22, 2024 5:53 PM
To: General Discussion: On-Topic and Off-Topic Posts <cctalk(a)classiccmp.org>
Cc: Eric Smith <spacewar(a)gmail.com>
Subject: [cctalk] Re: the 1968 how to build a working digital computer
On Sat, Jul 20, 2024 at 8:08 PM Steve Lewis via cctalk <
cctalk(a)classiccmp.org> wrote:
What I meant was that in the title of the book they
use "digital computer"
and I wonder if there was ever a book describing a mechanical "analog
computer" - and what they might even look like.
I haven't looked for a book, but if you'll settle for Wikipedia:
https://en.wikipedia.org/wiki/Differential_analyser
23 Jul
23 Jul
8:02 a.m.
On Jul 22, 2024, at 10:30 PM, dwight via cctalk
<cctalk(a)classiccmp.org> wrote:
At the last vcf here in California a fellow, I forget the name, brought in two tables
that connected together, could generate a damped sine wave. It used mostly Manco erector
like parts. It had some really great 0 backlash torque multipliers. They had to be finely
tuned so as to have almost 0 load on the integrating disk.
WW2 fire control computers were used on US battle ships. They had to compensate for
things like coriolis effects, mass, distance and charge.
Dwight
There are Navy training films online (on YouTube, I think) describing in some detail how
those machines worked.
paul
10:03 a.m.
On 2024-07-23 9:02 a.m., Paul Koning via cctalk wrote:
For the British and Commonwealth version search for "admiralty fire
control clock" or "admiralty fire control table" there seems to be a
fair bit of information about them online. My father-in-law told me
that on one ship he was on in the RCN his action station was at the wind
input on an admiralty fire control clock, this would likely have been
on the Tribal class destroyer HMCS Nookta.
Paul.
On Jul 22, 2024, at 10:30 PM, dwight via cctalk
<cctalk(a)classiccmp.org> wrote:
At the last vcf here in California a fellow, I forget the name, brought in two tables
that connected together, could generate a damped sine wave. It used mostly Manco erector
like parts. It had some really great 0 backlash torque multipliers. They had to be finely
tuned so as to have almost 0 load on the integrating disk.
WW2 fire control computers were used on US battle ships. They had to compensate for
things like coriolis effects, mass, distance and charge.
Dwight
There are Navy training films online (on YouTube, I think) describing in
some detail how those machines worked.
paul
11:34 a.m.
On Tue, Jul 23, 2024 at 1:53 AM Eric Smith via cctalk
<cctalk(a)classiccmp.org> wrote:
On Sat, Jul 20, 2024 at 8:08 PM Steve Lewis via cctalk <
cctalk(a)classiccmp.org> wrote:
There is a book, although finding it might well be a problem, at least
at a sensible price
The title is 'The Differential Analyser' by 'J. Crank'. I have the
1947 edition on my bookshelf, it desribes the non-Meccano machine at
Manchester University with photos and somewhat technical informtion on
how it worked.
-tony
What I meant was that in the title of the book
they use "digital computer"
and I wonder if there was ever a book describing a mechanical "analog
computer" - and what they might even look like.
I haven't looked for a book, but if you'll settle for Wikipedia:
https://en.wikipedia.org/wiki/Differential_analyser 
12:31 p.m.
On Mon, Jul 22, 2024 at 06:53:19PM -0600, Eric Smith via cctalk wrote:
On Sat, Jul 20, 2024 at 8:08?PM Steve Lewis via cctalk
<
cctalk(a)classiccmp.org> wrote:
For those who might be interested, here's a small manual for
the differential analyzer that was at the University of
Pennsylvania. That machine was used primarily by the Army
during WWII, but was made available for general use after
the war. This booklet appears to have been printed in 1952.
http://cs.drexel.edu/~bls96/eniac/other/diff-upenn.pdf
Please excuse the scan quality. This was scanned from
microfilm of the ENIAC trial exhibits. The pages with
photographs were particularly hard to set an intensity
curve that would mostly clear up the background but still
show some detail in the photos.
BLS
What I meant was that in the title of the book
they use "digital computer"
and I wonder if there was ever a book describing a mechanical "analog
computer" - and what they might even look like.
I haven't looked for a book, but if you'll settle for Wikipedia:
https://en.wikipedia.org/wiki/Differential_analyser 
20 Jul
20 Jul
4:41 a.m.
On 7/20/24 4:52 AM, Steve Lewis via cctalk wrote:
Has no one explored a "tri-state" system? (discrete regions across 5V?)
Do you mean ternary computers?
https://en.wikipedia.org/wiki/Ternary_computer
Former SU played with it a bit...
regards,
chris
2
days inactive
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days old
29 comments
19 participants
participants (19)
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dwight -
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John Herron -
Mike Begley -
Mike Katz -
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Paul Koning -
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Sellam Abraham -
Steve Lewis -
Tony Duell